A variety of methods are proposed for controlling the vibration damping property by the use of hydrocarbon resins; for example, commercial petroleum resins and coumarone-indene resins in JP63-11980 A and JP62-141069 A, commercial polybutene, terpene resin and modified rosin in JP2-49063 A and polycyclic aromatic resins or alkylbenzene-methylnaphthalene resins in JP7-90130 A.
A vibration-damping agent is incorporated in a base material such as rubber, resin and bitumen as an improver of the vibration-damping property and the resulting damping material is expected to show a large loss factor (tan δ) in the use range and minimal dependence of tan δ on temperature. However, these properties are often known to be contradictory.
The official gazette of WO01/16199 gives a description of a method for preparing polycyclic aromatic oligomers by the condensation reaction of a polycyclic aromatic compound containing 2 to 3 rings, a phenol and formaldehyde in the presence of an acid catalyst and also gives a description to the effect that the oligomers thus prepared are excellent vibration-damping agents.